Merge other tests from test_*path.py into test_genericpath.CommonTest, and do some cleanup.
diff --git a/Lib/test/test_macpath.py b/Lib/test/test_macpath.py
index b36ba00..d732e14 100644
--- a/Lib/test/test_macpath.py
+++ b/Lib/test/test_macpath.py
@@ -26,23 +26,6 @@
         self.assertFalse(isabs(b":foo:bar"))
         self.assertFalse(isabs(b":foo:bar:"))
 
-
-    def test_commonprefix(self):
-        commonprefix = macpath.commonprefix
-        self.assertEqual(commonprefix(["home:swenson:spam", "home:swen:spam"]),
-                         "home:swen")
-        self.assertEqual(commonprefix([":home:swen:spam", ":home:swen:eggs"]),
-                         ":home:swen:")
-        self.assertEqual(commonprefix([":home:swen:spam", ":home:swen:spam"]),
-                         ":home:swen:spam")
-
-        self.assertTrue(commonprefix([b"home:swenson:spam", b"home:swen:spam"])
-                     == b"home:swen")
-        self.assertTrue(commonprefix([b":home:swen:spam", b":home:swen:eggs"])
-                     == b":home:swen:")
-        self.assertTrue(commonprefix([b":home:swen:spam", b":home:swen:spam"])
-                     == b":home:swen:spam")
-
     def test_split(self):
         split = macpath.split
         self.assertEqual(split("foo:bar"),
@@ -54,36 +37,28 @@
         self.assertEqual(split(":conky:mountpoint:"),
                           (':conky:mountpoint', ''))
 
-        self.assertEquals(split(b"foo:bar"),
+        self.assertEqual(split(b"foo:bar"),
                           (b'foo:', b'bar'))
-        self.assertEquals(split(b"conky:mountpoint:foo:bar"),
+        self.assertEqual(split(b"conky:mountpoint:foo:bar"),
                           (b'conky:mountpoint:foo', b'bar'))
 
-        self.assertEquals(split(b":"), (b'', b''))
-        self.assertEquals(split(b":conky:mountpoint:"),
+        self.assertEqual(split(b":"), (b'', b''))
+        self.assertEqual(split(b":conky:mountpoint:"),
                           (b':conky:mountpoint', b''))
 
     def test_join(self):
         join = macpath.join
-        self.assertEquals(join('a', 'b'), ':a:b')
-        self.assertEquals(join('', 'a:b'), 'a:b')
-        self.assertEquals(join('a:b', 'c'), 'a:b:c')
-        self.assertEquals(join('a:b', ':c'), 'a:b:c')
-        self.assertEquals(join('a', ':b', ':c'), ':a:b:c')
+        self.assertEqual(join('a', 'b'), ':a:b')
+        self.assertEqual(join('', 'a:b'), 'a:b')
+        self.assertEqual(join('a:b', 'c'), 'a:b:c')
+        self.assertEqual(join('a:b', ':c'), 'a:b:c')
+        self.assertEqual(join('a', ':b', ':c'), ':a:b:c')
 
-        self.assertEquals(join(b'a', b'b'), b':a:b')
-        self.assertEquals(join(b'', b'a:b'), b'a:b')
-        self.assertEquals(join(b'a:b', b'c'), b'a:b:c')
-        self.assertEquals(join(b'a:b', b':c'), b'a:b:c')
-        self.assertEquals(join(b'a', b':b', b':c'), b':a:b:c')
-
-    def test_splitdrive(self):
-        splitdrive = macpath.splitdrive
-        self.assertEqual(splitdrive("foo:bar"), ('', 'foo:bar'))
-        self.assertEqual(splitdrive(":foo:bar"), ('', ':foo:bar'))
-
-        self.assertEquals(splitdrive(b"foo:bar"), (b'', b'foo:bar'))
-        self.assertEquals(splitdrive(b":foo:bar"), (b'', b':foo:bar'))
+        self.assertEqual(join(b'a', b'b'), b':a:b')
+        self.assertEqual(join(b'', b'a:b'), b'a:b')
+        self.assertEqual(join(b'a:b', b'c'), b'a:b:c')
+        self.assertEqual(join(b'a:b', b':c'), b'a:b:c')
+        self.assertEqual(join(b'a', b':b', b':c'), b':a:b:c')
 
     def test_splitext(self):
         splitext = macpath.splitext
@@ -95,27 +70,27 @@
         self.assertEqual(splitext(""), ('', ''))
         self.assertEqual(splitext("foo.bar.ext"), ('foo.bar', '.ext'))
 
-        self.assertEquals(splitext(b":foo.ext"), (b':foo', b'.ext'))
-        self.assertEquals(splitext(b"foo:foo.ext"), (b'foo:foo', b'.ext'))
-        self.assertEquals(splitext(b".ext"), (b'.ext', b''))
-        self.assertEquals(splitext(b"foo.ext:foo"), (b'foo.ext:foo', b''))
-        self.assertEquals(splitext(b":foo.ext:"), (b':foo.ext:', b''))
-        self.assertEquals(splitext(b""), (b'', b''))
-        self.assertEquals(splitext(b"foo.bar.ext"), (b'foo.bar', b'.ext'))
+        self.assertEqual(splitext(b":foo.ext"), (b':foo', b'.ext'))
+        self.assertEqual(splitext(b"foo:foo.ext"), (b'foo:foo', b'.ext'))
+        self.assertEqual(splitext(b".ext"), (b'.ext', b''))
+        self.assertEqual(splitext(b"foo.ext:foo"), (b'foo.ext:foo', b''))
+        self.assertEqual(splitext(b":foo.ext:"), (b':foo.ext:', b''))
+        self.assertEqual(splitext(b""), (b'', b''))
+        self.assertEqual(splitext(b"foo.bar.ext"), (b'foo.bar', b'.ext'))
 
     def test_ismount(self):
         ismount = macpath.ismount
-        self.assertEquals(ismount("a:"), True)
-        self.assertEquals(ismount("a:b"), False)
-        self.assertEquals(ismount("a:b:"), True)
-        self.assertEquals(ismount(""), False)
-        self.assertEquals(ismount(":"), False)
+        self.assertEqual(ismount("a:"), True)
+        self.assertEqual(ismount("a:b"), False)
+        self.assertEqual(ismount("a:b:"), True)
+        self.assertEqual(ismount(""), False)
+        self.assertEqual(ismount(":"), False)
 
-        self.assertEquals(ismount(b"a:"), True)
-        self.assertEquals(ismount(b"a:b"), False)
-        self.assertEquals(ismount(b"a:b:"), True)
-        self.assertEquals(ismount(b""), False)
-        self.assertEquals(ismount(b":"), False)
+        self.assertEqual(ismount(b"a:"), True)
+        self.assertEqual(ismount(b"a:b"), False)
+        self.assertEqual(ismount(b"a:b:"), True)
+        self.assertEqual(ismount(b""), False)
+        self.assertEqual(ismount(b":"), False)
 
     def test_normpath(self):
         normpath = macpath.normpath